LUMBAR RANGE OF MOTION - RELIABILITY AND VALIDITY OF THE INCLINOMETERTECHNIQUE IN THE CLINICAL MEASUREMENT OF TRUNK FLEXIBILITY

Study Design. This study examines the reliability and validity of meas uring lumbar range of motion with an inclinometer. Objectives. To find out whether a manual determination of the reference points for measur ing lumbar range of motion is as reliable as radiologic determination for positioning the inclinometers, lumbar range of motion was determin ed in degrees by evaluating radiographs and by using the inclinometer technique of Loebl. Summary of Background Data. Reliability and validi ty of the inclinometer technique as a clinical measurement of trunk fl exibility were investigated. Fifty-four patients participated in the s tudy. Methods. Lumbar range of motion measurements were taken with and without radiologic control of the T12 and S1 vertebrae as reference p oints for positioning of the inclinometers. An interrater correlation was done of the inclinometer techniques of a physician and a physiothe rapist. Functional radiographs were investigated in a standing positio n. Lumbar range of motion measurements based on radiographs and those taken using the inclinometer alone were correlated to validate the inc linometer technique. Results. Lumbar range of motion measurements take n with and without radiologic determination showed a very close correl ation (r = 0.93; P < 0.001). Flexion alone also demonstrated a close c orrelation (r = 0.95; P < 0.001), whereas extension showed a somewhat smaller correlation (r = 0.82; P < 0.001). Total lumbar range of motio n (r = 0.94; P < 0.001) and flexion (r = 0.88; P < 0.001) were closely related as indicated by the interrater correlation, whereas extension (r = 0.42; P < 0.05) showed a lesser correlation. Correlation of the measurements taken radiographically and by inclinometer demonstrated a n almost linear correlation for measurements of the total lumbar range of motion (r = 0.97; P < 0.001) and flexion (r = 0.98; P < 0.001), wh ereas extension (r = 0.75; P < 0.001) did not correlate as well. Concl usions. The noninvasive inclinometer technique proved to be highly rel iable and valid, but the measurement technique for extension needs fur ther refinement.